Two years ago the Boston Bruins rode a wave of good fortune, well-timed goals, and brilliant defense to their first Stanley Cup Finals victory in 39 years.

Their most important/best/publicly insane player was Tim Thomas, a then 36-year-old goalie who finished the regular season with the best save percentage (93.8%) and goals against average (2.00) in the league. He was an NHL All-Star, taking home the second Vezina Trophy of his career (of the nine goalies to win that award twice, only Charlie Hodge hasn’t been inducted into the Hall of Fame) and was awarded the Conn Smythe trophy for being the Most Valuable Player in the playoffs.

This season the Bruins are driven by those same Stanley Cup championship expectations and aspirations, except Thomas, who’s currently somewhere participating in non-hockey related activity in an isolated Colorado log cabin, will not be joining them. (Thomas was suspended by the team for sitting out the year.)

So why are the Bruins so confident in raising another Stanley Cup trophy despite their former savior being unavailable?

Insert Tuukka Rask, the one-time prodigious goaltender who Boston acquired in exchange for Andrew Raycroft seven years ago. It was an interesting deal at the time, as the Bruins decided to part ways with their goalie who was named Rookie of the Year just three seasons prior.

Raycroft was never the same after the lockout, and Boston’s decision to sell his stock before it could sink any lower was a wise one. In his first season as Toronto’s starting goalie, Raycroft allowed 208 goals, the most in the NHL.

The Bruins acquired Rask to be their goalie of the future, and with Thomas finally out of the picture, that future has arrived. Rask is 25 years old (13 years younger than Thomas) and until now has never before entered an NHL season as the undisputed starter in net.

Widely regarded as the best backup goaltender in the league last season, the 6’3” Rask was selected with the 21st overall pick in 2005. He was 18 years old. During the 2009-10 season, while filling in for an injured Thomas, he dominated would-be scorers, leading the league in save percentage and goals against average. He recorded five shutouts, the seventh most in the league. And played 13 games in the postseason, going 7-6 with a 91.2% save percentage and a 2.61 goals against average.

Rask is currently playing on a one-year, $3.5 million deal, gambling on the idea that he’ll have a great season, leading to even more money in a long-term deal next summer. It’s a risky bet, but both Rask and the Bruins are confident it’ll pay off.

(Through four games Rask has yet to lose, with an insanely good 1.96 goals against average.)

Rask’s save percentage and goals against averages last year were better than Thomas’ and despite only playing only a handful of playoff games in his career (all in 2010), there’s good reason to believe the Boston Bruins will once again have one of the best goalies in the league anchoring their stout defense.